The present invention relates to handle and exhaust duct coupling assemblies for floor care machines, such as vacuums, extractors, steam cleaners, and the like.
Many contemporary floor care machines are equipped with vacuum motors or other suction-generating apparatus for drawing particulates, fluids, or other materials from a floor surface and propelling such materials into a storage receptacle. Such floor care machines include upright and canister vacuums, extractors, steam cleaners, carpet shampooers, and other similar devices.
FIG. 1 is a side elevational, partially-exploded view of a floor care machine 20 (e.g. an upright vacuum) in accordance with the prior art. As is well known, the floor care machine 20 includes a head assembly 40 that engages a floor surface 22, and a dirt receptacle 26 for receiving and storing particulates. The head assembly 40 includes a vacuum unit 42 (not shown) that generates suction at the floor surface 22. An exhaust duct 28 extends upwardly from the head assembly 40. The exhaust duct 28 has a lower end 44 that is coupled to the vacuum unit 42 of the head assembly 40, and an upper end 46 that is coupled to a mid-handle connector 48 by a coupling assembly 50. The mid-handle connector 48 includes an exhaust outlet 29 that extends partially into the dirt receptacle 26. A handle support 30 is rigidly coupled to the mid-handle connector 48 by one or more fasteners 52 (e.g. screws, bolt, rivets, etc.). A handle grip 32 is attached to an upper end of the handle support 30.
In use, an operator grasps the handle grip 32 and actuates a control switch to transmit power to the vacuum unit 42. As will be understood by persons of ordinary skill in the art, the vacuum unit 42 creates suction within the suction compartment 60, drawing a particulate-laden airstream from the floor surface 12 through the intake aperture 64. The vacuum unit 42 propels the particulate-laden airstream through the head assembly 40, through the exhaust duct 28, through the mid-handle connector 48, and into the dirt receptacle 26, where the particulates may be filtered from the particulate-laden airstream and stored for later disposal. Floor care machines of the type shown in FIG. 1 are disclosed, for example, in U.S. Pat. No. 5,367,741 issued to Hampton et al, U.S. Pat. No. 5,230,121 issued to Blackman, U.S. Pat. No. 5,222,276 issued to Glenn, and U.S. Pat. No. 5,774,930 issued to Sommer et al.
FIG. 2 is an enlarged cross-sectional, assembled view of a coupling assembly 50 of the floor care machine 10 of FIG. 1. The coupling assembly 50 includes a collar 54 having an internal thread 56 and a partiallyconical sealing surface 58. A corresponding external thread 60 is disposed on the mid-handle connector 48. An xe2x80x9cOxe2x80x9d-ring seal 62 is positioned on the upper end 46 of the exhaust duct 28 between the collar 54 and the mid-handle connector 48. As the collar 54 is threadedly tightened onto the mid-handle connector 48, the sealing surface 58 presses the seal 62 into sealing engagement with the exhaust duct 28 and the mid-handle connector 48. Coupling assemblies 50 as shown in FIG. 2 are used, for example, in upright vacuum machines of the type generally disclosed, for example, in U.S. Pat. No. 6,033,451 issued to Fish et al.
Although desirable results have been achieved using such floor care machines, it may be desirable to further optimize the performance of these devices. For example, during use, the coupling assembly 50 is subjected to vibrational forces, torsional forces applied by the operator during pushing and pulling of the handle grip 32, and other loosening forces. After extended periods of use, the coupling assembly 50 may become loosened. As part of the maintenance of the machine, the operator may wish to check the collar 54 to prevent leakage from the exhaust duct 28. It may be advantageous, however, to reduce the operator""s maintenance responsibilities.
The present invention is directed to handle and exhaust duct coupling assemblies for floor care machines, such as vacuums, extractors, steam cleaners, and the like. In one aspect, an exhaust duct coupling assembly includes a first duct having an outer surface with an external thread disposed thereon and a locking tab projecting outwardly therefrom. A second duct is slideably engaged into the first duct, and a flexible seal is disposed about the second duct proximate an end of the first duct. A collar having a hole therethrough is disposed about the second duct and threadedly engaged with the end of the first duct. The collar presses the seal into an approximately sealing engagement against the second duct and the end of the first duct. The collar includes a locking surface frictionally engaged with the locking tab and inhibiting a disengaging movement of the collar.
Alternately, the locking surface of the duct coupling assembly may be an annular surface disposed on an inner surface of the collar, or may be disposed on an end surface of the collar. In another aspect, the collar may include a second locking surface engaged with the locking tab.
In yet another aspect, a handle coupling assembly includes a receiving member having an outer surface with an external thread disposed thereon and a plurality of bendable members projecting outwardly therefrom and at least partially surrounding a receiving space. A handle tube is disposed within the receiving space. A collar is disposed about the handle tube and threadedly engaged with the external thread. The collar bends the plurality of bendable members into engagement against the handle tube, thereby securing the handle tube into position.
Alternately, at least some of the bendable members include a retaining ridge projecting inwardly toward the receiving space, and the handle tube has a retaining groove circumferentially disposed therein, the retaining ridges projecting into the retaining groove. In a further aspect, the receiving member includes a locking tab projecting outwardly from the outer surface, and the collar includes a locking surface frictionally engaged with the locking tab and inhibiting a disengaging movement of the collar.